He cannot recuse himself without the hint of suspicion that he has a conflict of interest.
If he is being paid a full-time salary and wants to make extra money on the side, go to Wal-Mart and be a greeter. No conflict there.

But to do legal work on the side, while working full-time for the parish and making $183,900, means that we expect him to limit his work to full-time work for the parish.